[pytorch][PR] Add ability for a mobile::Module to save as flatbuffer (#70201)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/70201
Included functions:
save_mobile_module -> saves a mobile::Module to flatbuffer
load_mobile_module_from_file -> loads a flatbuffer into mobile::Module
parse_mobile_module -> parses from bytes or deserialized flatbuffer module object
Compared to previous attempts, this diff only adds flatbuffer to cmake target and leaves fbcode/xplat ones unchanged.
Test Plan: unittest
Reviewed By: malfet, gmagogsfm
Differential Revision: D33239362
fbshipit-source-id: b9ca36b83d6af2d78cc50b9eb9e2a6fa7fce0763
